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Effectiveness of Strengthening and Stretching Exercises for the Postural Correction of Abducted Scapulae: A Review

Hrysomallis, Con

The Journal of Strength & Conditioning Research: February 2010 - Volume 24 - Issue 2 - p 567-574
doi: 10.1519/JSC.0b013e3181c069d8
Brief Review

Hrysomallis, C. Effectiveness of strengthening and stretching exercises for the postural correction of abducted scapulae: a review. J Strength Cond Res 24(2): 567-574, 2010-Abnormal postural alignment can be detrimental to muscle function, is aesthetically unpleasing, and might contribute to joint pain. It has been unclear as to whether stretching or strengthening exercises can correct faulty posture such as abducted scapulae. It has been postulated that short and tight scapular abductor muscles or weak and lengthened scapular retractor muscles or a combination cause an abducted scapulae posture and that exercise can correct this condition. The purpose of this review was to compile the information on factors influencing scapular position at rest, examine the effectiveness of exercise interventions in altering scapular position, and make recommendations for future research. When examining the different methods that have been used to determine the position of the scapula, attention should be paid to their respective reliability and validity. Correlational studies have failed to detect a significant association between muscle strength and scapular position but found a significant relationship between muscle length and scapular position. Prospective intervention studies have shown that stretching the anterior chest muscles on its own or in combination with strengthening the scapular retractors can alter the position of the scapula at rest in individuals with abducted scapulae. Although these results are encouraging, there is a dearth of high-quality studies and more research is required to address the limitations of the studies. None of the intervention studies measured strength or flexibility pre or post intervention, so it is unclear how effective the intervention was in changing these factors and the actual mechanism behind the change. To determine which component of the intervention is most effective and whether the results are additive, future research should include stretching only, strengthening only, and combined stretching and strengthening groups. Follow-up measurements at some period after completion of the intervention would also provide important information as to the permanency of any changes. The practical implication is that caution must be displayed when considering the promotion of strengthening exercises to try and correct for abnormal scapular posture until further evidence becomes available.

Centre for Ageing, Rehabilitation, Exercise and Sport Victoria University, Melbourne, Australia

Address correspondence to Con Hrysomallis,

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Various professionals working in the strength and conditioning area may encounter clients or athletes who have concerns with their posture and seek exercise interventions for their correction. It has been assumed that exercise can correct faulty postural alignment, but an earlier general review found little evidence to support this assumption (8). Since that time, more studies have been published, particularly with regard to the alignment of the scapula. The objectives of the present review are to compile the information on factors influencing scapular position, examine the effectiveness of exercise interventions in altering scapular position, and make recommendations for future research. The review was based on articles identified by computerized searches using Medline (January 1966 to June 2007) and SportDiscus (January 1966 to June 2007) databases. The following search terms were used in various combinations: scapular, position, posture, and exercise. Other studies were identified from the reference list of the articles located by the electronic searches. Only articles that reported scapular position at rest were included in the review.

The position of the scapula at rest on the thorax will influence the functioning of muscles attached to it. Because the scapula is the origin and insertion of a number of muscles, its position will play a role in the muscles' length-tension relationship (27) and thus their efficiency. Abnormal scapular position may also alter the relationship at the glenohumeral joint and might be associated with shoulder pain or pathology (23,28). In addition, abnormal scapular alignment may be aesthetically unpleasing. “Rounded” or “forward shoulders” are terms commonly used to describe an abnormal scapular position. It usually refers to a combination of positions: The scapula is abducted in the frontal plane, and to conform to the curvature of the rib cage, it is also protracted in the sagittal plane, internally rotated about a vertical axis, and possibly elevated. Although the 3-dimensional nature of the position of the scapula is acknowledged, the term and measurement of “abducted scapulae” will be mainly used because it is considered to be the major component (4).

The optimal resting position of the scapula has not been firmly established, but it has been found that the medial border of the scapula is parallel to the spinous processes of the thoracic vertebrae, its upper edge is located at the level of the second or third thoracic vertebrae, and the inferior angle of the scapula sits at the level between the seventh and ninth thoracic vertebrae. The distance between the medial border of the scapula and the midline of the thorax has been reported to be about 8 cm (25), but this distance is dependent on the size of the individual and possibly best represented as a normalized value to account for differences in size (4).

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Anatomical Factors Affecting Resting Scapular Position

The scapula forms a functional joint with the thorax referred to as the scapulothoracic (ST) joint. Because it is not a true joint, it does not have some of the stabilizing factors of the other joints, such as ligaments or joint capsule. There is no direct osseous connection between the scapula and thorax. The clavicle connects to the acromion of scapula laterally and to the sternum medially. The concave anterior surface of the scapula rides over the convexity of the rib cage. Variations in the configuration of the clavicle, acromion, or rib cage can influence the position at the scapula. There are a number of muscles associated with the ST joint, located posteriorly are trapezius, levator scapulae, and rhomboids minor and major. Serratus anterior muscle is located laterally, whereas pectoralis minor is the only anterior muscle. When active, serratus anterior and pectoralis minor can abduct the scapula, the antagonists are trapezius, and the rhomboids.

It has been stated that scapular alignment at rest is maintained mainly by passive elements of the musculotendinous unit with only minimal-to-slight muscular activity (4). According to Kisner and Colby (11), the weight of the upper limb creates downward rotation, abduction, and forward tipping moment on the scapula. The downward rotation is countered by dynamic support of the upper trapezius and serratus anterior. Forward tipping and abduction are countered by dynamic support of the rhomboids and middle trapezius. Electromyographic (EMG) analysis has shown slight activity in upper trapezius and minimal activity in serratus anterior during relaxed standing (1).

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Proposed Etiology and Correction of Abnormal Scapular Posture

It has been postulated that prolonged static postures with the shoulders forward or excessive strengthening of the anterior chest muscles can result in abducted scapulae (24). Claims are made that certain activities or occupations may lead to abducted scapulae. Examples include swimmers (16), wheelchair athletes (3), weight trainers who focus on chest exercises (24), dentists (26), and musicians such as cello or double-bass players (24). Unfortunately, longitudinal prospective data on the influence of habitual posture on skeletal alignment are lacking.

Kendall et al. (9) state that individuals with forward shoulders have serratus anterior, pectoralis minor, and upper trapezius muscles in a shortened position, whereas middle and lower trapezius are in a lengthened position. Muscles in a shortened position are believed to be tight, whereas those in a lengthened position are weak. The treatment procedure recommended is to stretch pectoralis minor and strengthen middle and upper trapezius. Kisner and Colby (11) add support to this notion by stating that faulty scapular posture is associated with muscle length and strength imbalances and that a forward tilt of the scapula is linked with a tight pectoralis minor muscle and possibly weak serratus anterior or trapezius. Activation of the rhomboids and trapezius muscles is emphasized in treatment. Further agreement is provided by Sahrmann (24) stating that the most common cause of abducted-rotated scapular position is shortness of scapular abductors and this is associated with excessive length of the scapular retractors. Treatment includes improving scapular retraction and stretching pectoralis major and minor.

Individuals with abducted scapulae are believed to have short and tight scapular abductor muscles and lengthened and weak scapular retractors and this results in abnormal scapular alignment. To correct this condition, it is advised to stretch the scapular abductors and strengthen the scapular retractors. The underlying assumption is that muscle length or strength or both determine scapular position, so stretching a muscle will increase its resting length while strengthening a muscle, will decrease its resting length and alter skeletal alignment. To investigate the relationship between muscle strength or length and scapular position, a reliable and valid procedure is first required to determine scapular position.

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Determination of Scapular Position at Rest

There have been a number of studies that have examined the reliability and validity of determining the position of the scapula at rest, with the arm by the side of the body while standing (Table 1). Palpating and locating surface landmarks of the scapula and measuring the distances to surface landmarks of the vertebral spinous processes has been the most common technique. Investigators have used different scapular and vertebral surface landmarks. The amount of subcutaneous body fat may influence the ease and accuracy of landmark location (5). Intratester and intertester reliability has been reported for measurements within the same testing session. As expected, intratester reliability is usually higher than intertester. The experience and training of the tester may influence reliability (18).

Table 1

Table 1

Table 1

Table 1

Monitoring EMG activity has been infrequently used to promote a relaxed state before taking measurements (25). A tape measure has frequently been used to measure the distances, but some investigators have opted for unmarked sections of strings initially, so as to remove any measurer bias. Calipers have also been used (25) and may provide a more accurate linear distance because they do not need to conform to the contours of the body, as does a measuring tape or string.

The validity of determining scapular position has usually been assessed by comparison with radiographic measurements. Although assumed to be the “gold” standard, there are limitations with this method (13) and this is reflected in the reliability of repeated measurements taken from radiographs not always being high (6). The validity of the skin surface palpation technique using cadaver shoulders has been assessed by comparison with the actual location revealed by dissection, but there are limitations in inferring results from cadaver to living subjects (13). Data comparing direct measurements from cadaver shoulders with radiographic measurements are lacking. The method used to determine scapular position should ideally demonstrate high reliability (intraclass correlation coefficient [ICC] > 0.9) and validity (r > 0.9). Acceptable reliability and validity may be considered as >0.8 (21). As can been seen from Table 1, a range of reliability and validity values have been reported for the various techniques.

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Relationship Between Muscle Strength and Scapular Position

It has been assumed that the strength of the scapular abductor and retractor muscles may influence the position of the scapula, if the scapular abductors are strong and the retractors are relatively weak, this may promote excessive scapular abduction at rest. There has been one study (4) that investigated the relationship between scapular position at rest and the strength of middle trapezius and pectoralis minor muscles for 30 male and 30 female healthy subjects, mean age 26 years. Isometric peak force generated from a maximal contraction lasting 4 to 5 seconds was measured with a stabilized handheld dynamometer. It was positioned against the lateral aspect of the scapula for the middle trapezius test and against the anterior aspect of the shoulder for the pectoralis minor test. The normalized position of the scapula was determined as described in Table 1 for DiVeta et al. (4). It was found that there was no significant relationship between scapular position and middle trapezius force (r = 0.20), pectoralis minor force (r = 0.14), and ratio of muscle forces (r = 0.01). This study had a number of limitations. The intratester reliability of determining the normalized scapular position (ICC = 0.78) along with its validity (ICC = 0.73-0.79) reported in another study (6) was not high. The muscle strength tests were found to have high intratester reliability (ICC = 0.96), but their validity has not been established (15). The use of healthy subjects probably limited the range of scapular abduction position values and likelihood of detecting a relationship. The inclusion of subjects with excessive scapular abduction would have been desirable.

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Relationship Between Muscle Length and Scapular Position

The relative muscle length of the scapula abductors or retractors has been postulated to influence scapular position; short abductor or long retractor muscles may position the scapula in excessive abduction. To examine this possible link, the length of pectoralis minor muscle was measured in 50 healthy male and female subjects with a mean age of 27 years (2). Using palpation and a computerized electromagnetic measurement system, the distance between the coracoid process to the fourth rib adjacent to the sternum was used as the length of pectoralis minor at rest. This procedure was validated against cadaver measurements (ICC = 0.96), but reliability was not reported. Pectoralis muscle length was normalized by dividing by the subject's height, and subjects were then divided into 2 groups: the short pectoralis minor group with a length less than the mean minus 1 SD and the long pectoralis minor group with a length greater than the mean plus 1 SD.

Scapular position was determined by palpation and using a tape measure to determine 2 distances. The first was measured anteriorly between the sternal notch and coracoid process, and the second was measured posteriorly between the acromion and thoracic spine. The anterior measure was divided by the posterior measure to generate a scapula index. The reliability and validity of this value and its components were not established. The results revealed significant but low correlations between pectoralis minor length and sternal notch to coracoid process distance (r = 0.48) and scapula index (r = 0.37). There was no significant correlation (r = 0.17) between muscle length and distance between the acromion and thoracic spine. It is surprising that a significant relationship was found for the anterior measure but not the posterior, considering that the length of pectoralis minor would supposedly influence the position of the scapular landmarks.

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Effectiveness of Exercise Intervention on Altering Scapular Position

There have been studies examining the influence of stretching the scapular abductors or strengthening scapular retractors or a combination on the position of the scapula at rest (Table 2). All studies used subjects with some degree of forward shoulder posture. The study by Wang et al. (29) found no change in scapular position after 6 weeks of home-based strengthening and stretching exercises. The duration of the static stretches was 10 seconds. Roddey et al. (22) found that a 2-week stretching program of 30-second duration significantly reduced the resting scapular abduction position in subjects with moderate forward head/rounded shoulder posture. Kluemper et al. (12) used a 6-week supervised strengthening and stretching program and revealed that the intervention group significantly reduced forward shoulder posture. It seems that a supervised program may be more effective than a home-based one and that a stretch duration of 30 seconds is preferable to 10 seconds. There is also an indication that stretching the scapular abductors may be more important than strengthening the scapular retractors. Although changes in the position of the scapula were reported, there are notable weaknesses in the study designs. The techniques used to determine the position of the scapula displayed high reliability, but their validity is questionable, either not reported or r < 0.8. None of the studies measured strength or flexibility pre or post intervention, so it is unclear how effective the intervention was in influencing these parameters and the actual mechanism behind the change.

Table 2

Table 2

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Discussion and Conclusion

The question arises as to which properties of the muscle are most likely to influence scapular position. Bearing in mind the limitations of some of the research, the finding that muscle strength was not related to scapular position (4) may not be all that surprising because there is only low-level muscular activity about the scapula at rest. It is assumed that increased strength would lead to increased muscle tension at rest. It could be argued that a measure of muscular endurance is more likely to be related to scapular position than muscular strength, but then again, muscular strength might be reflective of muscular endurance. It needs to be noted that muscle tension on its own would not influence position unless there was a concurrent change in the resting length of the muscle. A significant relationship was reported (2) between pectoralis minor muscle length and scapular position. Forward shoulder posture was associated with shorter pectoralis minor length. Once again, the finding is not surprising because it is hard to envisage an abducted scapulae posture without short pectoralis minor length, and this on its own does not necessitate cause and effect. An individual with relatively short clavicles would present with an abducted scapulae posture, and the resting length of pectoralis minor would be short but not the cause of the posture. Short muscle length is more readily to be an influential factor if associated with greater musculotendinous stiffness. It could be more likely that a short stiff muscle would influence postural alignment. Resting muscle length, muscle range of motion, or EMG activity at rest does not necessarily provide an accurate measure of muscle stiffness at rest. There are active and passive elements that can contribute to musculoskeletal stiffness (14). Further investigation is required to determine any link between muscle stiffness and postural alignment.

Findings from the prospective intervention studies have shown that stretching the anterior chest muscles on its own (22) or in combination with strengthening exercises for the scapular retractors (12) can alter the position of the scapula at rest in individuals with abducted scapulae. Although these results are encouraging, more work is required in this area to address some of the limitations of these studies. Future research should employ reliable and valid methods to determine scapular position and pre- and post-intervention measures of muscular strength, endurance, resting length, and stiffness. To help determine which component of the intervention is most effective and if the results are additive, the intervention groups should include stretching only, strengthening only, and stretching and strengthening. The training sessions should be of progressive intensity and preferably supervised or a training diary kept of the subjects' adherence to the program and their perceived rate of exertion so as to monitor compliance and effort. A follow-up some period after completion of the intervention would also provide valuable information as to the permanency of any changes.

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Practical Applications

Although there are some data showing that stretching exercises may alter the position of the scapula at rest, the studies have limitations and further quality research is needed. The practical implication is that restraint should be practiced when considering the promotion of strengthening exercises for the correction of abnormal scapular posture until further evidence becomes available.

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No source of funding was used to assist in the preparation of this review. The author has no conflicts of interest that are directly relevant to the contents of this review.

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1. Basmajian, JV and Deluca, CJ. Posture. In: Muscles Alive: Their Function Revealed by Electromyography. 5th ed. Baltimore, MD: Williams & Wilkins, 1985. pp. 252-264.
2. Borstad, JD. Resting position variables at the shoulder: Evidence to support a posture-impairment association. Phys Ther 86: 549-557, 2006.
3. Burnham, RS, Curtis, KA, and Reid, DC. Shoulder problems in the wheelchair athlete. In: Athletic Injuries of the Shoulder. Pettrone, FA, ed. New York, NY: McGraw Hill, 1994. pp. 375-382.
4. DiVeta, J, Walker, ML, and Skibinski, B. Relationship between performance of selected scapular muscles and scapular abduction in standing subjects. Phys Ther 70: 470-479, 1990.
5. Gibson, MH, Goebel, GV, Jordan, TM, Kegerreis, S, and Worrell, TW. A reliability study of measurement techniques to determine static scapular position. J Orthop Sports Phys Ther 21: 100-106, 1995.
6. Greenfield, B, Catlin, PA, Coats, PW, Green, E, McDonald, JJ, and North, C. Posture in patients with shoulder overuse injuries and healthy individuals. J Orthop Sports Phys Ther 21: 287-295, 1995.
7. Host, HH. Scapular taping in the treatment of anterior shoulder impingement. Phys Ther 75: 803-812, 1995.
8. Hrysomallis, C and Goodman, C. A review of resistance exercise and posture realignment. J Strength Cond Res 15: 385-390, 2001.
9. Kendall, FP, McCreary, EK, Provance, PG, Rodgers, MM, and Romani, WA. Posture. In: Muscles Testing and Function With Posture and Pain. 5th ed. Baltimore, MD: Lippincott Williams & Wilkins, 2005. pp. 49-118.
10. Kibler, WB. The role of the scapula in athletic shoulder function. Am J Sports Med 26: 325-337, 1998.
11. Kisner, C and Colby, LA. The shoulder and shoulder girdle. In: Therapeutic Exercise: Foundations and Techniques. 5th ed. Philadelphia, PA: FA Davis, 2007. pp. 481-556.
12. Kluemper, M, Uhl, T, and Hazelrigg, H. Effect of stretching and strengthening shoulder muscles on forward shoulder posture in competitive swimmers. J Sport Rehabil 15: 58-70, 2006.
13. Lewis, J, Green, A, Reichard, Z, and Wright, C. Scapular position: The validity of skin surface palpation. Man Ther 7: 26-30, 2002.
14. Lieber, RL, Steinman, S, Barash, IA, and Chambers, H. Structural and functional changes in spastic skeletal muscle. Muscle Nerve 29: 615-627, 2004.
15. Michener, LA, Boardman, ND, Pidcoe, PE, and Frith, AM. Scapular muscle tests in subjects with shoulder pain and functional loss: Reliability and construct validity. Phys Ther 85: 1128-1138, 2005.
16. Murphy, TC. Shoulder injuries in swimming. In: The Athlete's Shoulder. Andrews, JR and Wilk, KE, eds. New York, NY: Churchill Livingstone, 1995. pp. 411-424.
17. Neiers, L and Worrall, TW. Assessment of scapular position. J Sport Rehabil 2: 20-25, 1993.
18. Nijs, J, Roussel, N, Vermeulen, K, and Souvereyns, G. Scapular positioning in patients with shoulder pain: A study examining the reliability and clinical importance of 3 clinical tests. Arch Phys Med Rehabil 86: 1349-1355, 2005.
19. Odom, CJ, Taylor, AB, Hurd, CE, and Denegar, CR. Measurement of scapular asymmetry and assessment of shoulder dysfunction using the lateral scapular slide test: A reliability and validity study. Phys Ther 81: 799-809, 2001.
20. Peterson, DE, Blankenship, KR, and Robb, JB. Investigation of the validity and reliability of four objective techniques for measuring forward shoulder posture. J Orthop Sports Phys Ther 25: 34-42, 1997.
    21. Polgar, S and Thomas, SA. Measurement and instrumentation. In: Introduction to Research in the Health Sciences. 4th ed. Edinburgh, Scotland: Churchill Livingstone, 2000. pp. 135-149.
    22. Roddey, TS, Olson, SL, and Grant, SE. The effect of pectoralis muscle stretching on the resting position of the scapula in persons with varying degrees of forward head/rounded shoulder posture. J Man Manipulative Ther 10: 124-128, 2002.
    23. Rupp, S, Berninger, K, and Hopf, T. Shoulder problems in high level swimmers-Impingement, anterior instability, muscular imbalance? Int J Sports Med 16: 557-562, 1995.
    24. Sahrmann, S. Movement impairment syndromes of the shoulder girdle. In: Diagnosis and Treatment of Movement Impairment Syndromes. St. Louis, MO: Mosby, 2002. pp. 193-245.
    25. Sobush, DC, Simoneau, GG, Dietz, KE, Levene, JA, Grossman, RE, and Smith, WB. The Lennie test for measuring scapular position in healthy young adult females: A reliability and validity study. J Orthop Sports Phys Ther 23: 39-50, 1996.
    26. Valachi, B and Valachi, K. Mechanisms leading to musculoskeletal disorders in dentistry. J Am Dent Assoc 134: 1344-1350, 2003.
    27. van der Helm, FC. Analysis of the kinematic and dynamic behaviour of the shoulder mechanism. J Biomech 27: 527-550, 1994.
    28. von Eisenhart-Rothe, R, Matsen, FA, Eckstein, F, Vogl, T, and Graichen, H. Pathomechanics in atraumatic shoulder instability: Scapular positioning correlates with humeral head centering. Clin Orthop Relat Res 433: 82-89, 2005.
    29. Wang, CH, McClure, P, Pratt, NE, and Nobilini, R. Stretching and strengthening exercises: Their effect on three-dimensional scapular kinematics. Arch Phys Med Rehabil 80: 923-929, 1999.

    resistance training; flexibility; rounded shoulders

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